Part connecting member, process cartridge, and electrophotographic image forming apparatus

ABSTRACT

In a part connecting member made from synthetic resin, at least two molded pieces obtained by the injection molding of plastic are provisionally connected by being adjacently arranged or abut against each other. The provisionally connected body is set in a die different from the dies used for the formation of each molded piece. Then, in a state such that each molded piece and the die are positioned, the molded pieces are joined by the injection of a molten resin material for joining into a gap formed between the opposed surfaces of the molded pieces that are adjacently arranged or abut against each other. An injection channel of the molten resin up to the gap is formed by using one of the molded pieces forming the gap of the opposed surfaces that are adjacently arranged or abut against each other.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to the configurations of an electrophotographic image forming apparatus adopting an electrophotographic image forming process such as a laser printer and an electrophotographic copying machine, and further relates to a process cartridge and the configuration of a part connecting member that is made from a synthetic resin and is for the use of the electrophotographic image forming apparatus and the process cartridge.

[0003] Hereupon, the electrophotographic image forming apparatus is a device for forming an image on a recording medium by adopting an electrophotographic image forming process. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (such as a laser printer, an LED printer and the like), a facsimile machine, a word processor and the like.

[0004] Incidentally, the process cartridge is a device that is made by the integration of charging means, developing means or cleaning means, and an electrophotographic photosensitive member as a cartridge which is detachably mountable to the main body of an electrophotographic image forming apparatus. And also, the process cartridge is a device that is made by the integration of at least one of charging means, developing means and cleaning means, and an electrophotographic photosensitive member as a cartridge which is detachably mountable to the main body of an electrophotographic image forming apparatus. Furthermore, a device that is made by the integration of at least developing means and an electrophotographic photosensitive member as a cartridge which is detachably mountable to the main body of an electrophotographic image forming apparatus is also called as the process cartridge.

[0005] 2. Description of the Related Arts

[0006] At first the outline of a conventional color laser printer is described on the basis of the cross section of FIG. 20.

[0007] In FIG. 20, reference numeral 105 designates a rotary developing apparatus including developing devices 105M, 105C, 105Y and 105B equipped with a magenta toner, a cyan toner, a yellow toner and a black toner, respectively. These four color developing devices 105M, 105C, 105Y and 105B are disposed rotatably around a shaft 105 e. Each center of the developing devices 105M, 105C, 105Y and 105B rotates in connection with a rotating gear disposed on the outer periphery of a revolving gear to keep their postures constant. Then, at the time of the formation of an image, one of the developing devices 105M, 105C, 105Y and 105B corresponding to a latent image stops at a position opposed to an image bearing member 104, and then a developing roller 105 b is positioned to be opposed to the surface of the image bearing member 104 with a narrow gap between them.

[0008] Then, at the time of developing, by the application of a bias voltage on the developing roller 105 b and by the rotation driving thereof, the developing roller 105 b develops the latent image on the image bearing member 104 to visualize the latent image as a toner image.

[0009] Now, a supply roller 105 a rubs against a developing roller 105 b, both being disposed in each of the developing devices 105M, 105C, 105Y and 105B. Each supply roller 105 a scrapes off the developer that did not contribute to the last development, and fresh developer is always supplied to the developing roller 105 b. A toner container for supplying developer to the developing roller 105 b is integrally provided to each of the developing devices 105M, 105C, 105Y and 105B. Hereupon, a conventional toner container is described.

[0010]FIG. 1B is a principal section showing a conventional toner container 40. A toner container 42 and a lid 41 of the toner container are joined by the flowing of the same resin into gaps 142 a and 142 b formed between molded pieces in a die in conformity with the die slide injection molding method using the same die at the molding process and the forming process, which method is disclosed in, for example, Japanese Examined Patent Publication No. 2-38377.

[0011] Flanges 143 a, 143 b, 143 c and 143 d are formed on the toner container 42 and the lid 41 at the gaps 142 a and 142 b between the molded pieces. Moreover, portions 144 a, 144 b, 144 c and 144 d recessed or projected in a die cutting direction are formed on the back surfaces of the flanges 143 a, 143 b, 143 c and 143 d intermittently or continuously along the lengthwise direction of the die. The portions 144 a, 144 b, 144 c and 144 d are engaged with prescribed portions in the die.

[0012] Furthermore, an entrance through which a material for joining is injected into the gaps between the molded pieces, or a gate 72 in the terminology of molding techniques, is formed on substantially an extension line of the gap 142 a, which is formed between frames, in a horizontal direction as shown in FIG. 7. Molten resin perpendicularly flows into the gap 142 a between the molded pieces from the horizontal direction through the gate 72 as indicated by an arrow 70.

[0013] However, in the conventional toner container, because the position of the entrance for injecting the material for joining into the gap between the molded pieces, which entrance is called as the gate in the terminology of molding techniques, should adjoin the gap, the direction of the injection of the resin is inevitably determined. Consequently, restriction on the designing of the die is tight.

[0014] The present invention is one that further improves the related art for resolving the aforesaid problem.

SUMMARY OF THE INVENTION

[0015] One object of the invention is to provide a part connecting member that realizes the improvement of molding workability, a process cartridge using the part connecting member, and an electrophotographic image forming apparatus that can detachably mount the process cartridge.

[0016] Another object of the invention is to provide a part connecting member in which the direction of the injection of resin can arbitrarily be determined, a process cartridge using the part connecting member, and an electrophotographic image forming apparatus that can detachably mount the process cartridge.

[0017] A further object of the invention is to provide a part connecting member that can improve the degree of freedom of the designing of dies to be used for molding, a process cartridge using the part connecting member, and an electrophotographic image forming apparatus that can detachably mount the process cartridge.

[0018] A still further object of the invention is to provide a part connecting member that realizes the improvement of the degree of freedom of the designing of a product, a process cartridge using the part connecting member, and an electrophotographic image forming apparatus that can detachably mount the process cartridge.

[0019] A still further object of the invention is to provide the configuration of a hollow body that is made from a resin and that has restriction on the designing of a product and the manufacturing of the product as little as possible for obtaining a product of high quality in a configuration formed by the following processes. That is, for example, at least two molded pieces obtained by the injection molding of plastic are provisionally connected by being adjacently arranged or abut against each other. The provisionally connected bodies are set in a die different from the dies used for the formation of each molded piece. Then, in a state such that each molded piece and the die are positioned, the molded pieces are joined by the injection of a molten resin material for joining into a gap formed between the opposed surfaces of the molded pieces that are adjacently arranged or abut against each other.

[0020] A still further object of the invention is to provide a part connecting member, and a process cartridge and an electrophotographic image forming apparatus, both using the part connecting member made from a synthetic resin. One of the molded parts forming a gap between opposed surfaces that are adjacently arranged or abut against each other forms an injection channel of a molten resin up to a connection portion in configuration formed by the following processes. That is, at least two molded pieces obtained by the injection molding of plastic are provisionally connected by being adjacently arranged or abut against each other. The provisionally connected body is set in a die different from the dies used for the formation of each molded piece. Then, in a state such that each molded piece and the die are positioned, the molded pieces are joined by the injection of the molten resin into the gap formed between the opposed surfaces of the molded pieces that are adjacently arranged or abut against each other.

[0021] A still further object of the invention is to provide a part connecting member, and a process cartridge and an electrophotographic image forming apparatus, both using the part connecting member made from a synthetic resin, and the part connecting member comprises a first to a fourth frames being severally a molded piece. The third and the fourth frames form an injection channel of a molten resin up to a connection portion in the following configuration. That is, the part connecting member is configured by provisionally connecting side faces of the first frame and the second frame on one end side and the other end side of the frames in a state of being adjacently arranged or abut against each other with the third frame and the fourth frame, first. Then, the provisionally connected member is set in a die different from dies used for formation of each of the molded pieces. Moreover, a molten resin is injected in a gap formed between opposed surfaces of the molded pieces that are adjacently arranged or abut against each other to connect the molded pieces in a state such that each of the molded pieces and the die are positioned a gap.

[0022] A still further object of the invention is to provide a part connecting member, and a process cartridge and an electrophotographic image forming apparatus, both using the part connecting member made from a synthetic resin, and the part connecting member is configured in conformity with the following processes. That is, at least two molded pieces obtained by the injection molding of plastic are provisionally connected by being adjacently arranged or abut against each other. The provisionally connected member is set in a die different from the dies used for the formation of each molded piece. Then, in a state such that each molded piece and the die are positioned, the molded pieces are joined by the injection of a molten resin material for joining into a gap formed between the opposed surfaces of the molded pieces that are adjacently arranged or abut against each other. A portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into the gap is not all of the peripheries of the gap.

[0023] A still further object of the invention is to provide a part connecting member, and a process cartridge and an electrophotographic image forming apparatus, both using the part connecting member made from a synthetic resin, and the part connecting member comprises a first to a fourth frames being severally a molded piece. The third frame and the fourth frame provisionally connect the side faces of the first and the second frames on one end side and the other end side of the frames in a state of being adjacently arranged or abut against each other. Then, the provisionally connected member is set in a die different from dies used for the formation of each of the molded pieces. Moreover, a molten resin is injected to connect the molded pieces into a gap formed between opposed surfaces of the molded pieces that are adjacently arranged or abut against each other in a state such that each of the molded pieces and the die are positioned. A portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into the gap is not all of the peripheries of the gap.

[0024] These and other objects, features and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025]FIG. 1A is a longitudinal section of a hollow body made from a resin according to Embodiment 1 of the present invention;

[0026]FIG. 1B is a longitudinal section of a conventional hollow body made from a resin;

[0027]FIG. 2 is a perspective view of a hollow body according to Embodiment 2 of the present invention;

[0028]FIG. 3 is a view looking in the direction of the arrow III in FIG. 2;

[0029]FIG. 4 is a cross section taken along a IV-IV line in FIG. 3;

[0030]FIG. 5 is a cross section taken along a V-V line in FIG. 3;

[0031]FIG. 6 is a partially enlarged view of FIG. 4;

[0032]FIG. 7 is a longitudinal section showing a runner and a gate of a reference example;

[0033]FIG. 8 is a cross section taken along the IV-IV line in FIG. 3 showing the relation between a gate of a die and a resin channel;

[0034]FIG. 9 is a cross section taken along the IV-IV line in FIG. 3 showing the relation between a gate of a die and a resin channel (in the case where products are closely disposed);

[0035]FIG. 10 is a cross section showing another embodiment related to the vicinity of an inflow opening of the resin channel;

[0036]FIG. 11 is a plan view of container parts when dies are removed in FIG. 10;

[0037]FIG. 12 is a longitudinal section showing the relation between dies for joining of the invention and container parts to be joined;

[0038]FIG. 13 is a longitudinal section showing a state in which the container parts are set in the dies for joining and a resin is injected into a gap formed by opposed surfaces of approached or touched molded pieces;

[0039]FIG. 14 is a longitudinal section showing the gap of the Embodiment 1 of the invention;

[0040]FIG. 15 is a longitudinal section showing the gap of the Embodiment 1 of the invention;

[0041]FIG. 16 is a longitudinal section of a printer;

[0042]FIG. 17 is a longitudinal section of a process cartridge;

[0043]FIG. 18 is a disassembled perspective view of the process cartridge;

[0044]FIG. 19 is a perspective view of the process cartridge; and

[0045]FIG. 20 is a longitudinal section of a conventional electrophotographic image forming apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] The preferred embodiments of the present invention are described in the following on the basis of the attached drawings.

[0047] An embodiment of the present invention in which four container parts are joined is described on the basis of FIG. 16 to FIG. 19. The join of the four container parts means the fixation of a toner container (second frame) and a cleaning container (first frame) with side covers (a third and a fourth frames) on a front side (F side) and a rear side (R side). The lengthwise direction of the embodiment means a direction parallel to a direction that is perpendicular to the conveying direction of a recording medium and is parallel to the surface of the recording medium.

[0048] (Descriptions of Process Cartridge and Main Body of Apparatus)

[0049]FIG. 17 shows the principal section of a process cartridge according to the present invention, and FIG. 16 shows the principal section of an electrophotographic image forming apparatus according to the invention. The process cartridge is equipped with an electrophotographic photosensitive member and process means for acting on the electrophotographic photosensitive member. Now, as the process means, there are, for example, charging means for charging the surface of the electrophotographic photosensitive member, a developing device for forming a toner image on the electrophotographic photosensitive member, and cleaning means for removing the residual toner on the surface of the electrophotographic photosensitive member.

[0050] The process cartridge 13 of the present embodiment is configured, as shown in FIG. 17, by the disposition of a charging roller as the charging means 17 around a photosensitive drum 15 as the electrophotographic photosensitive member that is an image bearing member, a developing roller 20 s and a developing blade 20 b as the developing means, and the cleaning container 14 with a cleaning blade 16 as the cleaning means, and by the integral covering of them with a housing. The process cartridge 13 is configured to be detachably mountable to the main body 18 of the image forming apparatus (hereinafter referred to as apparatus main body ).

[0051] The process cartridge 13 is mounted on an electrophotographic image forming apparatus C that is shown in FIG. 16 to be used for the formation of an image. At the formation of an image, a transferring material 2 is conveyed with a feed roller 3 from a feed cassette 1 mounted at the lower part of the apparatus, and then a latent image is formed by the selective exposure to the photosensitive drum 15 from a scanner 30 in synchronism with the conveyance of the transferring material 2. After that, triboelectification charges are induced on the toner contained in a toner container 50 by the developing blade 20 b, and the toner is borne on the surface of the developing roller 20 s as a thin layer. Then, a bias voltage for development is improved on the developing roller 20 s to supply the toner on the photosensitive drum 15 correspondingly to the latent image. A toner image is transferred to the transferring material 2, which is a recording medium to be transported, by the imposed bias voltage on a transfer roller 10. The transferring material 2 is transported to a fixing device 25 to fix the image. And then, the transferring material 2 is delivered to a delivery portion 24 disposed at the upper part of the apparatus with delivery rollers 34 and 35. On the other hand, after the transferring, residual toner on the photosensitive drum 15 is removed with the cleaning blade 16, and the removed toner is transported to a removed toner reservoir 14 d with a carrying member 14 e of the removed toner.

[0052] (Frame Configuration of Process Cartridge)

[0053]FIGS. 18 and 19 are perspective vies showing the frame configuration of the process cartridge. FIG. 18 shows a state before the assembling of these frames, and FIG. 19 shows a state after the assembling of these frames. The process cartridge 13 is composed of three frames. The three frames are the cleaning container 14 supporting the photosensitive drum 15, the charging roller as the charging means 17 and the cleaning blade 16 integrally, a developing frame 19 supporting the developing roller 20 s and the developing blade (not shown in FIG. 18. See reference numeral 20 b in FIG. 17.) integrally, and the toner container 50 containing toner. Furthermore, for the integral support of these three frames, side covers 37 and 38 fix both the sides of the cleaning container 14 and the toner container 50, severally, and the developing frame 19 is supported by the cleaning container 14 to consist of the process cartridge 13.

[0054] The cleaning blade 16 is fixed to the cleaning container 14 with small screws or the like, and the charging means 17 supports core metal portions at ends with a bearing member (not shown) rotatably. Moreover, the cleaning container 14 is removably provided with the carrying member 14 e for carrying the removed toner that was removed with the cleaning blade 16 to the removed toner reservoir 14 d as shown in FIG. 17. Moreover, flange portions 15 a and 15 b on both the ends of the photosensitive drum 15 are supported by the cleaning container 14 with bearing members 39 a and 39 b (only the bearing member 39 a is shown in FIG. 18) fixed on the cleaning container 14, respectively. The toner container 50 contains toner together with agitating members 50 e and 50 f (see FIG. 17) for conveying and agitating the toner in the toner container 50.

[0055] The side covers 37 and 38 have such a size as cover the principal section of the process cartridge 13 (a perpendicular surface along the transporting direction of recording media), and are disposed at both the ends of the process cartridge 13 in the lengthwise direction thereof. The side covers 37 and 38 cover the cleaning container 14 and the toner container 50 to be fixed on the cleaning container 14 and the toner container 50 from their both sides for supporting the cleaning container 14 and the toner container 50 integrally. Respective hole portions 37 a and 38 a of the side covers 37 and 38 are positioned on the same axis as the center of the photosensitive drum 15 in the cleaning container 14. On the side cover 37 side shown in the figures, the bearing member 39 a is force-fitted into a hole portion 14 a of the cleaning container 14. A shaft member 43 is fitted into the hole portion 37 a of the side cover 37, the bearing member 39 a, and the center hole 15 a 1 of the flange 15 a to support one end of the photosensitive drum 15 rotatably. Because the positioning of the side cover 37 is performed with the bearing member 39 a at this time, the position of the side cover 37 to the photosensitive drum 15 can precisely be determined. Moreover, a positioning portion 37 b that is formed at a position as far as possible from the photosensitive drum 15 is fitted into a positioning portion 14 b formed on the side face 14 c of the cleaning container 14, and then the position of the rotation direction is determined around the center of the photosensitive drum 15 as the center thereof.

[0056] Furthermore, cylindrical positioning portions 50 a and 50 b are formed on one end surface 50 d in the lengthwise direction of the toner container projectingly in the lengthwise direction, and the positioning portions 50 a and 50 b are fitted into positioning portions 37 c and 37 d that are holed disposed on the side cover 37 to performed the positioning of the toner container 50. The side cover 38 on the other side similarly positions the toner container 50 and the cleaning container 14 (reference signs 38 a, 38 b, 38 c and 38 d). The developing frame 19 determines its position in a method that will be described later. Moreover, the bearing members 39 (39 a, 39 b) are also used for the positioning of the process cartridge 13 to the apparatus main body 18.

[0057] Opening portions 50 c (see FIG. 17) and 19 a are formed in the toner container 50 and the developing frame 19, respectively, for supplying toner to the developing roller 20 s from the toner container 50. The developing frame 19 and the toner container 50 is connected to each other with a flexible seal member 44 as a sealing member for the connection of the opening portions 19 a and 50 c to each other. Because the toner container 50 is positioned to the side covers 37 and 38 and the developing frame 19 is positioned to the cleaning container 14, and further because there are some dimension errors between the developing frame 19 and the toner container 50 on the other hand, it is necessary to arrange the developing frame 19 and the toner container 50 with a little gap. Then, the process cartridge 13 is positioned for the mounting thereof on the cartridge mounting portion of the apparatus main body 18 on the cleaning container 14 side supporting the photosensitive drum 15. Because the weight difference of the toner container 50 between a case where the toner container 50 contains a great deal of toner and a case where the toner container 50 is vacant is large, there is the possibility that the toner container 50 or both of or either of the side covers 37 and 38 is distorted. Accordingly, a flexible material is used for the seal member 44.

[0058] (Configuration of Developing Frame)

[0059] The configuration of the developing frame 19 is described by reference to FIGS. 17 and 18.

[0060] The developing frame 19 is provided with the developing roller 20 s involving a magnet roller 20 a (see FIG. 18) as a developer bearing member and the developing blade 20 b. Both ends of the developing roller 20 s are rotatably supported by the developing frame 19. Moreover, the developing roller 20 s is configured such that the electric power supply to the developing roller 2 is performed through an electric contact point formed in the developing roller 20 s.

[0061] The developing frame 19 is supported by the cleaning container 14 in such a way that the developing frame 19 can swing around a hanging hole 19 d at the end of an arm portion 19 c formed on the driving side, one of the ends of the developing roller 20 s in the lengthwise direction, in order that the center of the developing roller 20 s moves toward the center of the photosensitive drum 15. That is, the developing frame 19 including the developing roller 20 s is disposed on the driving side of the cleaning container 14 in a state such that the developing roller 19 can swing around a not shown pin that is fitted to the hanging hole 19 d. And the cleaning container 14 and the toner container 50 are fixed in a state such that they can relatively move. Consequently, the developing frame 19 can move relatively to the toner container 50. Then, one end side of the developing roller 20 s is energized to one end side of the photosensitive drum 15 with a helical extension spring hung between not shown spring pegs formed on the cleaning container 14 and the developing frame 19, severally.

[0062] Furthermore, a projecting member 19 e is fixed on the central axis of the developing roller 20 s on the non-driving side of the developing frame 19, and the projecting member 19 e is configured to be pressured to the center direction of the photosensitive drum 15.

[0063] The projecting member 19 e is inserted in a groove 37 e (an elongated hole having a shape of a straight line in a radial direction of the photosensitive drum 15 in the present embodiment) formed on the side cover 37, and the projecting member 19 e is configured such that the projecting member 19 e can move in the center direction of the photosensitive drum 15. That is, the projecting member 19 e is a moving member moving on the one end of the developing roller 20 s. Moreover, a not shown helical compression spring that is an energizing member is provided in order to pressure the projecting member 19 e with a slide piece, which is put between the helical compression spring and the projecting member 19 e and is movable along the groove 37 e.

[0064] The aforesaid side covers 37 and 38 have a shape of a container, and the sides of the side covers 37 and 38 that are opposed to the end surfaces 50 d of the toner container 50 and the side faces 14 c of the cleaning container 14 are opened. Edges 37 h and 38 h of the side covers 37 and 38 are connected with edges 50 h and 14 h of the end surfaces 50 d of the toner container 50 and the side faces 14 c of the cleaning container 14. For the connection, any one of Embodiment 1 to Embodiment 9 is applied.

[0065]FIG. 4 and FIG. 6 show an embodiment of the present invention, and FIG. 7 shows a reference example for illustrating the embodiment of the invention.

[0066] Next, the embodiments of the invention are shown. Incidentally, the numbers of the embodiments are not linked to the numbers of claims.

[0067] (Embodiment 1)

[0068]FIG. 1A, FIG. 12 and FIG. 13 show Embodiment 1. Embodiment 1 is described by reference to FIGS. 1A, 12 and 13.

[0069] Embodiment 1 has the following configuration made in conformity with the following processes. That is, a container part 51 as the main body of the toner container and a container part 52 as the lid, which are at least two molded pieces obtained by the injection molding of plastic, are approached or touched to each other in dies 200 a and 200 b different from the not shown dies that were used for the formation of the molded pieces. The approached or touched molded pieces are joined by the injection of a molten resin material for joining into gaps 154 formed between opposed surfaces of the molded pieces. Consequently, the joining of a plurality of parts becomes possible, and the freedom of designing is improved. And further, the assembling of the parts becomes simplified.

[0070] In FIGS. 1A and 1B, the arrow S indicates a projection direction of the hollow body made of resin. When the hollow bodies are projected in the direction indicated by the arrow S, a projected area of the hollow body made of resin in FIG. 1A can be made larger than a projected area of the hollow body made of resin in FIG. 1B.

[0071] The joined portions are not all of the gaps formed by the opposed surfaces of the approached or touched molded pieces. This is an indispensable matter for the decrease of the amount of deformation of a joined body. Moreover, the adoption of a configuration such that the flow of resin is stopped by a rib formed in a direction to prevent a resin channel (that is, in a direction perpendicular to the channel) makes it possible to select a portion where joining is performed intentionally.

[0072] If the gaps 154 are formed on the entire circumferences of the molded pieces, an amount of shrinkage of the poured resin in the flowing direction thereon may become large (the resin is shrunk as the resin drops in temperature from the melting temperature), and thus, there is the possibility that the molded pieces to be joined are deformed. Accordingly, as shown in FIG. 14 or FIG. 15, a rib 400 for stopping resin is formed in each of the gaps 154. The rib may preferably be formed perpendicularly to the flow direction of the molten resin in each of the gaps 154 (154 a, 154 b, 154 c and 154 d) formed by the opposed surfaces of the approached or touched molded pieces. However, the direction is not necessary to be perpendicular, but may be any direction as long as the rib can stop the flow of the molten resin. Consequently, at the places where the rib 400 for stopping resin exists, a notch is formed in each of ribs 160 (160 a, 160 b, 160 c and 160 d) for preventing the interference with the rib 400 for stopping resin. Or, as shown in FIG. 15, the ribs 400 for stopping resin are formed into a shape 400 a having a notch for preventing the interference with the ribs 160. The thing for stopping resin is now called as a rib, but even a rib having a large width (in the lengthwise direction of the gap formed by the opposed surfaces of the approached or touched molded pieces) and not having a so-called rib has a function for stopping resin. Consequently, the present invention includes such a case. The positions of the ribs 400 are, for example, near the corners of the container part 52 as the lid of the toner container as shown in FIG. 2.

[0073] (Embodiment 2)

[0074] As shown in FIG. 1A and FIG. 2, in a configuration in which at least two container parts 51 and 52 as molded pieces obtained by the injection molding of plastic are approached or touched to each other in dies and the container parts 51 and 52 are joined by the injection of a molten resin material for joining into gaps 154 a and 154 b, the constitution of the joining portions are composed of flange portions 152 a, 152 b, 152 c and 152 d formed on the approached or touched container parts 51 and 52 and ribs 160 a, 160 b, 160 c and 160 d formed in the die cutting direction from the flange portions 152 a, 152 b, 152 c and 152 d, respectively. Moreover, in addition to the ribs 160 a, 160 b, 160 c and 160 d, the configuration includes ribs 161 a and 161 b, formed in the die cutting direction like the ribs 160 a, 160 b, 160 c and 160 d, for preventing the deformation of the ribs 160 b and 160 d formed in the die cutting direction from the container part 51 having the flange portions 152 b and 152 d at the time of the injection of the molten resin material for joining into the gaps 154 a and 154 b. Consequently, the container 50 having the flange portions 152 b and 152 d shorter than those of the conventional container 40 has less restrictions on the designing of a product by that extent like the following.

[0075] That is, because it becomes possible to increase the internal volume G thereof, it also becomes possible to decrease the projected area thereof as a unit as a result.

[0076] And, at the time of manufacturing (molding), the configuration for die cutting can also be selected.

[0077] (Embodiment 3)

[0078] As shown in FIG. 1A and FIG. 9, Embodiment 3 has a configuration in which the thicknesses of the ribs 160 a and 160 b (160 c and 160 d) formed in the die cutting direction from the flange portions 152 a and 152 b (152 c and 152 d) formed on each of the container parts 51 and 52 are within a range of 0.3 mm to 2.5 mm in the joining configuration of Embodiment 2. Consequently, when a material for joining is injected into the gaps 154 a and 154 b, the ribs 160 a and 160 b (160 c and 160 d) are deformed perpendicularly to the flowing direction of the material and radially by the pressures working from the centers of the gaps 154 a and 154 b, and then the ribs 160 a and 160 b respectively adhere to the die 200 a and the supporting rib 161 a formed on the container part 52 being the other party. Consequently the material for joining injected into the gaps 154 a and 154 b does not leak in the inside of the container 50.

[0079] (Embodiment 4)

[0080] Embodiment 4 has a configuration in which the cross-sectional areas 55 (see FIG. 13) perpendicular to the resin flowing direction at the molten resin injection portions are severally within a range of 1 m² to 9 mm² in the joining configuration of Embodiment 2. Consequently, the cross-sectional areas 55 of the gaps 154 a and 154 b as the molten resin injection portions can be determined on the basis of bonding strength and the length (region) L (see FIG. 2) where joining is desired. In the region L, the container part 51 as the main body of the toner container and the container part 52 as the lid of the toner container have parts adhere to each other and parts at which the container parts 51 and 52 are integrally connected with each other with the gaps 154.

[0081] (Embodiment 5)

[0082]FIG. 1A is a longitudinal section of a hollow body made from a resin also according to Embodiment 5. Incidentally, because the longitudinal section perpendicular to FIG. 1A is also a similar configuration except that the largeness thereof in the horizontal direction is different, the longitudinal sections are described by reference to FIG. 1A representatively.

[0083]FIG. 1A shows Embodiment 5 of the present invention, and FIG. 1B shows a conventional hollow body for the comparison with Embodiment 5 of the invention.

[0084] Two container parts 51 and 52, which are obtained by the injection molding of plastic and are severally a molded piece, are approached or touched to each other in not shown dies, and the container parts 51 and 52 are joined to each other by the injection of a molten resin material for joining into the gaps 154 a and 154 b.

[0085] Now, Embodiment 5 has the flange portions 152 a, 152 b, 152 c and 152 d at the portions where the container parts 51 and 52 are severally approached or touched to each other. The flange portions 152 b and 152 d of one container part 51 on the upper side are provided with the ribs 160 b and 160 d that are ribs formed in the die cutting direction along the edge of the container part 51 and are touched to the flange portion 152 a and 152 c of the other container part 52 on the lower side.

[0086] The ribs 160 b and 160 d of the container part 51 vertically extends (in the die cutting direction). Moreover, the inner wall 51 b of the container part 51 is situated on the same planes as each side face on one side of the ribs 160 b and 160 d. The flange portions 152 b and 152 d of the container part 51 are outside flanges on the outer periphery side of the container part 51, and have horizontal flange surfaces 152bl and 152dl. The thicknesses of the ribs 160 b and 160 d perpendicular to the die cutting direction are within a range of 0.3 mm to 2.5 mm. The top faces of the ribs 160 b and 160 d are horizontal planes. The corners of the ribs 160 b and 160 d on the inside of the container part 51 are chamfered (chamfering C).

[0087] The flange portions 152 a and 152 c of the other container part 52 on the lower side are provided with ribs 160 a, 160 c formed along the edges of the container part 52 in the die cutting direction. The gaps 154 a and 154 b are defined by the ribs 160 a, 160 c and the ribs 160 b, 160 d of the container part 51. The ribs 160 a and 160 c abut against the flange portions 152 b and 152 d of the container part 51, respectively. The ribs 160 b and 160 d of the container part 51 respectively abut against the horizontal flange surfaces 152 a 1 and 152 c 1 of the flange portions 152 a and 152 c. Herein, the ribs 160 a and 160 c are formed in the die cutting direction (vertical direction).

[0088] The container part 52 on the lower side is provided with the ribs 160 a and 160 c in parallel to each of the ribs 161 a and 161 b, which will be described later, respectively. The ribs 160 a and 160 c have outer side faces flush with the tips of the flanges 152 a and 152 c, respectively. The flange portions 152 a and 152 c are situated on the outer periphery side of the container part 52. The ribs 160 b and 160 d of the container part 51 come in contact with the flange surfaces 152 a 1 and 152 c 1 of the flange portions 152 a and 152 c, respectively. The thicknesses of the ribs 160 a and 160 c perpendicular to the die cutting direction are within a range of 0.3 mm to 2.5 mm.

[0089] Each height of the ribs 160 a, 160 b, 160 c and 160 d formed on the flange portions 152 a ,152 b, 152 c and 152 d of the container parts 51 and 52 from the flange surfaces 152 a 1, 152 b 1, 152 c 1 and 152 d 1 is the same.

[0090] Corners of respective ribs 160 a, 160 b, 160 c and 160 d on the base side on the side of the gaps 154 a and 154 b are severally rounded in a radius r (the reference sign r is denoted in FIG. 1B only one side). The heights of the ribs 160 b and 160 d of the container part 51 and the ribs 160 a and 160 c of the container part 52 are the same. Consequently, in a state such that the molten resin for joining is not injected into the gaps 154 a and 154 b, the gaps 154 a and 154 b are spaces having a rectangular shape in section and severally have a radius at a corner on one diagonal position.

[0091] Each of the ribs 160 a, 160 b, 160 c and 160 d are formed in such a way that they surround the edges of the container parts 51 and 52. That is, any of the shapes of the edges of the container parts 51 and 52 cut vertically in the inside to outside direction is the same as FIG. 1A.

[0092] Now, the cross-sectional areas of the gaps 154 a and 154 b are within a range of 1 to 9 mm². Because the cross-sectional areas of the gaps 154 a and 154 b are substantially a square, the height of each of the ribs 160 a, 160 b, 160 c and 160 d is about 1 to 3 mm.

[0093] The other container part 52 is provided with the supporting ribs 161 a and 161 b on the inside of the respective ribs 160 b and 160 d of the container part 51 for the prevention of the ribs 160 b and 160 d to the inside 60 a of the container 50 at the time of the injection of the molten resin material into the gaps 154 a and 154 b. The ribs 161 a and 161 b have the side faces on the same planes of the inner walls 52 a and 52 b of the container part 52.

[0094] The container part 52 has one plane inner walls 52 a and 52 b, and the inner walls 52 a and 52 b extend over the flange portions 152 a and 152 c as the side faces of the supporting ribs 161 a and 161 b. The heights of the supporting ribs 161 a and 161 b is substantially the same as the amount of the heights of the gaps 154 a and 154 b formed upwardly from the positions of the flange surfaces 152 a 1 and 152 c 1 added to the heights of the thicknesses of the flange portions 152 b and 152 d of the container part 51, respectively. The thicknesses of the supporting ribs 161 a and 161 b are set to be substantially equal to the thicknesses of the container part 52. That is, when force is applied to the supporting ribs 161 a and 161 b owing to the deformations of the ribs 160 b and 160 d as it will be described later, it is necessary to reduce the deformation quantities of the supporting ribs 161 a and 161 b themselves to be small.

[0095]FIG. 1A shows an embodiment of the present invention, and FIG. 1B shows the related art.

[0096] Provided that the widths of the completed synthetic resin hollow body of both of the containers of the related art and the embodiment of the present invention are the same now. In FIGS. 1A and 1B, two dotted lines are parallel lines and severally pass through the end surfaces of the flanges showing the widths of the related art and the present invention. In the related art, the inner dimensions of the lid 41 of the toner container and the toner container 42 in the width direction are the same, “W”. In the embodiment of the present invention, the size W1 between the inner walls 51 b, which is the inner dimension of the container part 51, is larger than the distance W between the inner walls of the toner container 42 of the related art. Moreover, the distance W2 between the inner walls of the container part 52 is equal to the distance W between the inner walls of the related art. Moreover, the heights of the synthetic resin hollow bodies of the related art and the present embodiment are the same.

[0097] Consequently, if the sizes in the lengthwise directions of the toner container 42 of the related art and the synthetic resin hollow body of the present embodiment are the same, the internal volume G of the present embodiment as a container is larger than the internal volume E of the related art.

[0098] Next, the operation of the configuration at the time of the injection of a molten resin for joining is described. In the embodiment, any runner is not shown.

[0099] A preferable embodiment for forming a runner and a gate is described later. In any case, the molten resin for joining flows into the gaps 154 a and 154 b through the molten resin injection portions communicating between the outside and the gaps 154 a and 154 b. Although the ribs 160 b and 160 d of the container part 51 is deformed toward the inside of the container 50 owing to the pressure operating from the centers of the gaps 154 a and 154 b, which are formed by the opposed surfaces of the container parts 51 and 52 that are adjacently arranged or abut against to each other radially and perpendicularly to the flowing direction of the molten resin at the time of the injection thereof, the deformation is prevented by the adhesion of the ribs 160 b and 160 d to the supporting ribs 161 a and 161 b, and further the ribs 160 b and 160 d pressure the ribs 161 a and 161 b, respectively, to improve the rigidity and the strength of the container 50. Moreover, the ribs 160 a and 160 c of the container part 52 incline to deform to the outside of the container 50 owing to the aforesaid pressure of the molten resin at the gaps 154 a and 154 b, but the inclination is prevented by the abutting of the outside faces of the ribs 160 a and 160 c against not shown dies. Incidentally, it is better that the heights of the supporting ribs 161 a and 161 b from the flange surfaces 152al and 152cl are higher than at least the heights of the ribs 160 b and 160 d. On the other hand, it is better that the supporting ribs 161 a and 161 b are lower for the increase of the internal volume G of the inside 60 a.

[0100] Incidentally, although the ribs 160 a and 160 c on the side of the outer periphery of the container part 52 is pressured by the molten resin in the gaps 154 a and 154 b being resin channels, the deformed ribs 160 a and 160 c abut against the dies. Accordingly, smaller values in the aforesaid range of the thicknesses can be adopted as the thicknesses of the ribs 160 a and 160 c.

[0101] Incidentally, for example, high impact polystyrene can be adopted as the material of the container parts 51 and 52. Moreover, for example, polystyrene PS not including flame-retardant additives are adopted as the material to be injected for joining.

[0102] (Embodiment 6)

[0103] Embodiment 6 forms resin injection channels up to the gaps 154 a and 154 b on a container part on one side. Because the configuration of the ribs around the gaps 154 a and 154 b is the same as that of Embodiment 5, the descriptions concerning Embodiment 5 are quoted to the configuration of the ribs of Embodiment 6.

[0104]FIG. 2 is a perspective view showing the whole of Embodiment 6. FIG. 3 is a view looking in the direction of the arrow III in FIG. 2. FIG. 4 is a cross section taken along a IV-IV line in FIG. 3. FIG. 5 is a cross section taken along a V-V line in FIG. 3.

[0105] Embodiment 6 adopts the following configuration. That is, the resin injection channels up to the gaps formed by the opposed surfaces of the container parts that are adjacently arranged and abut against each other are formed on a container part on one side, and the channels penetrate between the gaps and the outside of the container part perpendicularly to the resin flowing directions in the gaps. The penetration direction is the assembling direction at the time of the combining of the container parts.

[0106] As shown in FIG. 2, molten resin inflow openings 200 d of molten resin injection channels 200 are formed at the positions of the container part 51 on the upper side according to the gates of dies. That is, in the present embodiment in which resin injection channels 200 are formed in one of the container parts 51 and 52, the inflow openings 200 d are formed in the container part 51 correspondingly to the intermediate points in the directions along the edges of the container part 51 of the respective flange portions 152 (152 a, 152 b, 152 c and 152 d) of the container part 51. The same is said of the resin injection channels 200 formed toward the gaps in the respective flanges. In the following, descriptions are given to the gap 154 a.

[0107] As shown in FIG. 4, the resin injection channel 200 is formed perpendicularly to the resin flowing direction in the gap 154 a. In Example 6, the channel 200 is vertical. The channel 200 penetrates the container part 51 between an outside surface 51 a of the container part 51 and the gap 154 a. For the formation of the channel 200, a pillar-shaped portion 51 c is formed from the flange portion 152 b to the outside surface 51 a in the container part 51 (see FIG. 2). The plane shape of the pillar-shaped portion 51 c is an arc around a center axis x of the channel 200 as shown in FIG. 3, and the corners thereof at the joining points with the outside surface of the base material of the container part 51 are rounded to be arcs R.

[0108] The channel 200 has a tapered shape such that the inflow opening 200 d side of the channel 200 is formed as a bigger diameter portion and the gap 154 a side of the channel 200 is formed as a smaller diameter portion 200 c.

[0109] As shown in FIG. 5, although the relational positions of the respective ribs 160 a, 160 b and 161 a are the same as those of Embodiment 1, the corner of the base side of the supporting rib 161 a of the container part 52 on the lower side is not rounded. Corner chamfering R1 and an inclined plane SL are formed on the supporting rib 161 a in order that the rib 160 b of the container part 51 on the upper side can easily enter into the side face of the supporting rib 161 a when the container parts 51 and 52 are assembled such that the parts 51 and 52 are adjacently arranged or abut against each other. Thereby, the side face on the end side of the rib 160 b of the container part 51 adheres to the side face on the base side of the supporting rib 161 a along the line of the side face of the rib 161 a owing to the pressure of the resin flowing into the gap 154 a. Consequently, the supporting ribs and the ribs of the container part 51 adhere to each other over the entire circumference of the joining portions of the container parts 51 and 52.

[0110] According to the embodiment, because gate portions of dies can be connected with the molten resin injection channels 200 on the outside surface 51 a side of the container part 51, as shown in FIG. 7, it is not necessary to provide the side gate 72 adjacently to the gap 142 a, and the dies for the use of the joining of the container parts 51 and 52 can be reduced from the point of view of projected areas of products. On the contrary, in the related art shown in FIG. 7, because the side gate 72 is disposed on the side of the gap 142 runners should be provided in radial directions from the outside of the lid 41 of the container and the body 42 of the container. Consequently, the dies are large.

[0111] According to the present embodiment, as shown by an arrow Q in FIG. 4, a gate of a die can be connected with the inflow opening 200 d of the resin injection channel 200. Then, when a molten resin flows into the channel 200, the resin is not caked on the midway of the channel 200 and the gate sealing is performed in the vicinity of the small diameter portion 200 c where the gap 154 a and the channel 200 intersect each other, because the channel 200 is in a shape of a taper. Consequently, because the resin injected into the gap 154 a under a pressure does not flow backward to the channel 200, the resin in the gap 154 a is caked in a state in which the ribs 160 a and 160 b are respectively pressured by the die 200 a (see FIG. 9) and the supporting rib 161 a.

[0112] (Embodiment 7)

[0113] According to Embodiment 6, the resin flowing in the channel 200 flows like an arrow 71 b shown in FIG. 6 at the gap 154 a and collides with the flange portion 152 a of the container part 52. Thereby, a force P acts on the flange portion 152 a owing to the variation of the kinetic momentum of the molten resin. Because the flow velocity of the resin flowing in channel 200 is large and the mass of the resin is also large, the force P becomes large.

[0114] Accordingly, in the present embodiment, as shown in FIG. 9, an undersurface 171 a of the flange 152 a of the container part 52 on the lower side is supported by a supporting surface 202 b formed on the die 200 b for the support of the container part 52.

[0115] As described above, because the supporting surface 202 b of the die 200 b is formed such that the supporting surface 202 b crosses the extension line of the center axis x passing through the gate of the die 200 a and the channel 200, the pressure imposed on the flange portion 152 a by the jet stream of the injected resin material does not cause a quality problem of the deformation of the flange portion 152 a because the flange portion 152 a is supported by the supporting surface 202 b of the die 200 b. Moreover, restrictions on manufacturing such as the selection of a high flow material, the increase of the number of gates, and the like are not generated. Even if the injection pressure of the molding of the container 50 and so forth is set at a pressure higher than an ordinary pressure, the quality problems such as deformation are not generated in units after joining.

[0116] Because the velocity energy of the resin flowing in the resin channel being the gap formed by the opposed surfaces between the container parts that are adjacently arranged and abut against each other is rapidly lost to be converted into a static pressure, the static pressure becomes a large pressure pressuring the peripheral walls of the gap. However, as mentioned above, the ribs of the container part on the upper side is supported by the ribs of the container part on the lower side.

[0117] In the present embodiment, the joining configuration of the container is as follows. That is, the thicknesses of the ribs 160 a, 160 b, 160 c and 160 d formed in the die cutting direction from the flange portions 152 a, 152 b, 152 c and 152 d formed on the container parts 51 and 52 are within a range of 0.3 mm to 2.5 mm. When a material for joining is injected into the gaps 154 a and 154 b, the ribs 160 a, 160 b, 160 c and 160 d are deformed by the pressure acting from the center of the gaps 154 a and 154 b perpendicularly an radially to the flowing direction, and the ribs 160 a, 160 b, 160 c and 160 d respectively adhere to the die 200 a and the supporting ribs 161 a and 161 b formed on the other party container part. Thereby, there is no case where the material for joining that has flown into the gaps 154 a and 154 b leaks inside or outside the container 50. Although the supporting ribs 161 a and 161 b is pressured by the molten resin in the gaps 154 a and 154 b with the ribs 160 b and 160 d put between them at this time, the pressure is decreased owing to the deformation of the ribs 160 a and 160 d. Then, after the adhesion of the ribs 160 a and 160 d and the supporting ribs 161 a and 161 b, the ribs 160 a and 160 b and the supporting ribs 161 a and 161 b are cooperatively oppose the pressure from the molten resin in the gaps 154 a and 154 b. Incidentally, the thicknesses of the supporting ribs 161 a and 161 b are substantially the same as that of the base material of the container part 52 in the present embodiment.

[0118] Next, Embodiment 8 in which sealing performance between the gates of a die and molded pieces being container parts is heightened around gates is described.

[0119] (Embodiment 8)

[0120]FIG. 8 and FIG. 9 show Embodiment 8.

[0121] Embodiment 8 prevents the leakage of resin to the outside at a portion where the resin injection channel 200 is connected with a gate in the case where such a channel is formed as shown in Embodiment 7. In Embodiment 8, the tip portion of a die at which a gate in the terminology of molding techniques, which is an inlet of a molten resin material for joining, is formed accords with the outside surface of the inlet of the resin channel of a container part forming the resin channel or is recessed in the resin channel from the outside surface.

[0122] As shown in FIG. 8, the respective center axes x of the gate 201 formed in the die 200 a and the resin injection channel 200 of the container part 51 on the upper side align with each other. Supposed that the diameter of the inflow opening 200 d of the channel 200 is “g”, a truncated cone portion 303 having the center of the center axis x projects downward from the under surface 200al of the die 200 a. The gate 201 is formed in the die 200 a such that an inlet 201 a is situated at the top surface of the truncated cone portion 303. Incidentally, the under surface 200 a 1 of the die 200 a is in parallel with the outside surface 51 a of the container part 51 on the upper side.

[0123] In the embodiment mentioned above, if the diameter of the top portion of the truncated cone portion 303 is fl and the diameter of the bottom portion thereof is f2, the diameter g of the inlet portion of the resin injection channel 200 satisfies the relation: f2>g>f1. In FIG. 8, the diameter f1 is set to be indefinitely close to the diameter g of the inlet portion. The inner diameter of the inflow opening 200 d of the resin injection channels 200 is within a range of 1.5 mm to 3.00 mm, and the inner diameters of the portions facing the gaps 154 and at which molten resin flows into the gaps 154 are within a range of 0.8 mm to 2.5 mm. That is, the channel 200 is formed as a taper having a large diameter portion of the inflow opening 200 d. The taper is 1 degree to 6 degrees when it is expressed by the angle.

[0124] In FIG. 8, when the die 200 a is moved downward, the top portion of the truncated cone portion 303 is brought into pressure contact with the circumference edge of the inflow opening 200 d of the channel 200 of the container part 51 to deform the portion around the opening 200 d and to seal the portion connecting the gate 201 with the channel 200. Consequently, the molten resin does not leak to the outside from the portion between the inlet 201 a of the gate 201 and the opening 200 d of the channel 200.

[0125] In the form shown in FIG. 9, a chamfering 300 adhering to the truncated cone portion 303 is previously formed on the container part 51 around the opening 200 d of the channel 200. Also in such a configuration, the molten resin does not leak from the portion where the opening 200 d of the channel 200 is connected with the gate 201 of the die 200 a. That is, the truncated corn portion 303 is closely pressed against the chamfering 300 of the opening 200 d. In the state such that the truncated cone portion 303 is pressed against the chamfering 300, the container part 51 and the under surface 200 a 1 of the die 200 form gaps 301 a and 301 b.

[0126] In the embodiment shown in FIG. 9, the insertion amount h of the truncated cone portion 303 being the tip portion of the die forming the gate 201 into the inside of the inflow opening 200 d from the outside surface 51 a in the inflow opening 200 d portion of the resin injection channel 200 of the container part 51 is within 10 mm.

[0127] As mentioned above, a sealing portion in the shape of a cone surface for sealing a portion between a die and a container part by pressing the die forming a gate against an inlet of a resin injection channel of the container part closely. Thereby, the molten resin does not leak out from the gate of the die and the inlet of the resin injection channel of the container part.

[0128] The die 200 a reaches, as shown in FIG. 9, the lower part of the portion appearing to the outside of the contact surface of the flange surface 152bl of the container part 51 on the upper side with the rib 160 a of the container part 52 on the lower side to approach to the side face of the container parts 51 and 52.

[0129] In the above descriptions, although the truncated cone portion is dealt as a part of the cone, the portion around the gate is not necessarily the cone, but the portion may be configured with a cone being a rotation body having a generating line of a curve of second order that is approximate to a straight line.

[0130] (Embodiment 9)

[0131]FIG. 10 shows Embodiment 9.

[0132] The whole shape of the joining portion of Embodiment 9 is substantially same as FIG. 2, but the configuration around an inflow opening of the resin injection channel 200 of Embodiment 9 differs from that of FIG. 2.

[0133] A cylindrical projection portion 306 b projects downward from a die 300 a for pressing the container part 51 on the upper side. A cylindrical recessed portion 306 a is formed at the center of the cylindrical projection portion 306 b, and the inlet 201 a of the gate 201 is situated at the center of a truncated cone portion 303 formed at the center of the bottom surface of the cylindrical recessed portion 306 a.

[0134] A cylindrical boss 305, which fits in the cylindrical recessed portion 306 a of the die 300 a with a gap, is formed around the inflow opening of the resin injection channel 200 of the container part 51. In a state such that the peripheral surface of the truncated cone portion 303 of the die 300 a is pressed against the circumference of the inlet portion of the resin injection channel 200, the tip of the cylindrical projection portion 306 b of the die 300 a is separated from the container part 51. Besides, the portions of the die 300 a other than the portion where the circumference of the inlet portion of the resin injection channel 200 is in contact with the truncated cone portion 303 around the inlet 201 a of the gate 201 are sufficiently separated from the container part 51 on the upper side except for the portions of the die 300 a corresponding to the flange 152 a of the container part 51 and the rib 160 a of the container part 52 on the lower side.

[0135] In the present embodiment, a cylindrical recessed portion having a diameter larger than that of the inlet of a gate is formed continuously to the gate outside the inlet of the gate of a die; and a cylindrical boss, which is fitted to the recessed portion with a gap, and the tip of which abuts against the bottom of the recessed portion, is formed around the inlet of a resin channel of a container part. If a resin is injected from the inlet of the resin injection channel 200 to the gaps 154 a and 154 b formed by the container parts 51 and 52 toward the gaps 154 a and 154 b, and if a force acts on the container part 51 forming the resin injection channel 200 in the direction of the outer periphery of the container part 51, the outer periphery of the cylindrical boss 305 around the inflow opening of the resin injection channel 200 of the container part 51 and the inner periphery of the cylindrical recessed portion 306 a of the die 300 a closely adhere to each other. Consequently, the resin does not leak out to the outside of the container part 51 owing to the cracking and the like of the container part 51.

[0136] The gap between the cylindrical recessed portion 306 a of the die 300 a and the cylindrical boss 305 around the inflow opening of the resin injection channel 200 is preferably 0.3 mm or less.

[0137] The process cartridge shown in FIG. 18 is assembled as follows. That is, both the side faces in lengthwise direction of the cleaning container 14 being the first frame integrating the cleaning blade 16, the charging means 17 and the photosensitive drum 15 and both the side faces in lengthwise direction of the toner container 50 being the second frame integrating the agitating members 50 e and 50 f and a developer are provisionally combined with the side covers 37 and 38 being the third frame and the fourth frame in a state such that the cleaning container 14 and the toner container 50 are adjacently arranged or abut against each other (same as the state shown in FIG. 19). After that, the provisionally combined bodies are fitted into the aforesaid dies and positioned. In such a state, a molten resin is injected into the gaps formed by the opposed surfaces of the container parts that are adjacently arranged or abut against each other for joining. Or, the side covers 37 and 38 may be adjacently arranged or abut against each other in the dies after the integration of the cleaning container 14 and the toner container 50 in the dies.

[0138] In this case, the molten resin injection channels 200 (continuing the inflow openings 200 d although the channels 200 are not shown in FIG. 18) are formed on the side covers.

[0139] Incidentally, the definitions of words and phrases that are used for the descriptions of the present embodiments are briefly described in the following.

[0140] “Provisional connection” means the connection lest the dies for joining should be separated at the time of insertion by the use of a snap fit, fittings, a jig and the like.

[0141] “Adjacent arrangement” means the arrangement of two parts with a gap being 1.5 mm or less between them.

[0142] Abutting means the state such that no gap is formed between two parts.

[0143] A gap formed by the opposed surfaces between the container parts means a gap formed by the opposed surfaces having an area substantially within a range of 1 mm²to 13 mm². However, the phrase is not necessarily interpreted to be within the range when the phrase is used in claims. The range may appropriately be modified according to the contents of the invention.

[0144] As described above, because, in the configurations of the aforesaid embodiments, resin is injected from the outside of a unit molded piece, positions to be joined are not restricted to the outer peripheries of the gaps formed by the opposed surfaces of the container parts that are adjacently arranged or abut against each other. That is, the positions to be joined can arbitrarily be set.

[0145] Furthermore, when a material not including flame-retardant additives is adopted as an injection material to be used for joining, high flow and flame-retardant gases are not generated. Consequently, high cohesive strength can be obtained.

[0146] Furthermore, when ribs for preventing the flow of resin are formed in resin inflow portions of the gaps formed by the opposed surfaces between container parts that are adjacently arranged or abut against each other, the resin can be stopped by the ribs. That is, intentional selection of joining portions becomes possible.

[0147] According to the aforesaid embodiments, the aforesaid configurations of hollow bodies made from synthetic resin and their manufacturing methods can obtain preferable effects when they are applied to an electrophotographic image forming apparatus, a toner supplying container and a process cartridge.

[0148] As described above, according to the present invention, workability can be improved.

[0149] While the invention has been described with reference to the structure disclosed herein, it is not confined to the details set forth and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims. 

What is claimed is:
 1. A part connecting member made from a synthetic resin, said member being to be used in a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, wherein an injection channel for the molten resin up to said gap is formed in one of said molded pieces forming said gap of the opposed surfaces that are adjacently arranged or abutted against each other.
 2. A part connecting member made from a synthetic resin, said member being to be used in a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, wherein an injection channel for the molten resin up to said gap is formed in said third frame and said fourth frame.
 3. A part connecting member according to claim 1 or 2, wherein said injection channel is formed in the one of said molded pieces, and said injection channel communicates said gap with an outside of the one of said molded pieces, the outside being situated in a direction that is perpendicular to a flowing direction of the molten resin in said gap and is an assembling direction at a time of provisional connection of said molded pieces.
 4. A part connecting member according to any one of claims 1-3, wherein an inner diameter of an inlet of said injection channel formed in the one of said molded pieces is within a range of 1.5 mm to 3.00 mm, said inlet being situated on an outer side when said part connecting member is formed, and an inner diameter at a portion of said injection channel where the molten resin flows into said gap is within a range of 0.8 mm to 2.5 mm.
 5. A part connecting member according to any one of claims 1-4, wherein said injection channel formed in the one of said molded pieces has an inlet on a side being an outside when a process cartridge is formed and an inner diameter being smaller than that of said inlet, said inner diameter being at a portion where the molten resin flows into said gap, and said injection channel is tapered within a range of one degree to six degrees.
 6. A part connecting member made from a synthetic resin, said member being to be used in a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap.
 7. A part connecting member made from a synthetic resin, said member being to be used in a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap.
 8. A part connecting member according to claim 6 or 7, further comprising a rib disposed in said gap and extending in a direction substantially perpendicular to a resin flowing direction to block a flowing path.
 9. A part connecting member according to any one of claims 1-8, wherein the molten resin is polystyrene without flame-retardant additives.
 10. A part connecting member according to any one of claims 1-9, wherein said gap for forming a connecting portion is formed at a predetermined position within an projected area of each part forming said part connecting member.
 11. A process cartridge detachably mountable to a main body of an image forming apparatus, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame has a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein an injection channel for the molten resin up to said gap is formed in one of said molded pieces forming said gap of the opposed surfaces that are adjacently arranged or abutted against each other.
 12. A process cartridge detachably mountable to a main body of an image forming apparatus, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, wherein an injection channel for the molten resin up to said gap is formed in said third frame and said fourth frame.
 13. A process cartridge according to claim 11 or 12, wherein said injection channel is formed in the one of said molded pieces, and said injection channel communicates said gap with an outside of the one of said molded pieces, the outside being situated in a direction that is perpendicular to a flowing direction of the molten resin in said gap and is an assembling direction at a time of provisional connection of said molded pieces.
 14. A process cartridge according to any one of claims 11-13, wherein an inner diameter of an inlet of said injection channel formed in the one of said molded pieces is within a range of 1.5 mm to 3.00 mm, said inlet being situated on an outer side when said part connecting member is formed, and an inner diameter at a portion of said injection channel where the molten resin flows into said gap is within a range of 0.8 mm to 2.5 mm.
 15. A process cartridge according to any one of claims 11-14, wherein said injection channel formed in the one of said molded pieces has an inlet on a side being an outside when said process cartridge is formed and an inner diameter being smaller than that of said inlet, said inner diameter being at a portion where the molten resin flows into said gap, and said injection channel is tapered within a range of one degree to six degrees.
 16. A process cartridge detachably mountable to a main body of an image forming apparatus, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap.
 17. A process cartridge detachably mountable to a main body of an image forming apparatus, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap.
 18. A process cartridge according to claim 16 or 17, further comprising a rib disposed in said gap and extending in a direction substantially perpendicular to a resin flowing direction to block a flowing path.
 19. A process cartridge according to any one of claims 11-18, wherein the molten resin is polystyrene without flame-retardant additives.
 20. A process cartridge according to any one of claims 11-19, wherein said gap for forming a connecting portion is formed at a predetermined position within an projected area of each part forming said part connecting member.
 21. An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising: (a) mounting means for mounting said process cartridge, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame has a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein an injection channel for the molten resin up to said gap is formed in one of said molded pieces forming said gap of the opposed surfaces that are adjacently arranged or abutted against each other; and (b) transporting means for transporting the recording medium.
 22. An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising: (a) mounting means for mounting said process cartridge, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein an injection channel for the molten resin up to said gap is formed in said third frame and said fourth frame; and (b) transporting means for transporting the recording medium.
 23. An electrophotographic image forming apparatus according to claim 21 or 22, wherein said injection channel is formed in the one of said molded pieces, and said injection channel communicates said gap with an outside of the one of said molded pieces, the outside being situated in a direction that is perpendicular to a flowing direction of the molten resin in said gap and is an assembling direction at a time of provisional connection of said molded pieces.
 24. An electrophotographic image forming apparatus according to any one of claims 21-23, wherein an inner diameter of an inlet of said injection channel formed in the one of said molded pieces is within a range of 1.5 mm to 3.00 mm, said inlet being situated on an outer side when said part connecting member is formed, and an inner diameter at a portion of said injection channel where the molten resin flows into said gap is within a range of 0.8 mm to 2.5 mm.
 25. An electrophotographic image forming apparatus according to any one of claims 21-24, wherein said injection channel formed in the one of said molded pieces has an inlet on a side being an outside when said process cartridge is formed and an inner diameter being smaller than that of said inlet, said inner diameter being at a portion where the molten resin flows into said gap, and said injection channel is tapered within a range of one degree to six degrees.
 26. An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising: (a) mounting means for mounting said process cartridge, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two molded pieces obtained by injection molding of plastic are provisionally connected by being adjacently arranged or abutted against each other, the provisionally connected molded pieces are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap; and (b) transporting means for transporting the recording medium.
 27. An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising: (a) mounting means for mounting said process cartridge, said process cartridge comprising: an electrophotographic photosensitive drum; process means for acting on said electrophotographic photosensitive drum; and a frame member made by joining a plurality of molded pieces for supporting said electrophotographic photosensitive drum or said process means, wherein said frame member has a construction in that at least two kinds of frames including a first frame and a second frame, both being molded pieces, are provisionally connected so as to be adjacently arranged or abutted against each other by a third frame and a fourth frame, both being molded pieces, at side faces of said first and second frames on one end side and the other end side, the provisionally connected frames are set in dies which are different from a die used for formation of each of said molded pieces, and a molten resin is injected into a gap formed between opposed surfaces of said molded pieces that are adjacently arranged or abutted against each other to connect said molded pieces in a state that each of said molded pieces and said dies are in position, and wherein a portion of the opposed surfaces to be connected with the molten resin when the molten resin is flown into said gap is not an entire circumference of said gap; and (b) transporting means for transporting the recording medium.
 28. An electrophotographic image forming apparatus according to claim 26 or 27, further comprising a rib disposed in said gap and extending in a direction substantially perpendicular to a resin flowing direction to block a flowing path.
 29. An electrophotographic image forming apparatus according to any one of claims 21-28, wherein the molten resin is polystyrene without flame-retardant additives.
 30. An electrophotographic image forming apparatus according to any one of claims 21-29, wherein said gap for forming a connecting portion is formed at a predetermined position within an projected area of each part forming said part connecting member. 